<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title></title>
  <link rel="stylesheet" href="./layout.css">
</head>
<body>
<form id="main">
  <lable>宽度</lable>
  <input type="number" id='width' min="0" autofocus required step='0.01'><span></span>
  <br>
  <div id='kuan'></div>
  <lable>高度</lable>
  <input type="number" id='height' min="0" required step="0.01"><span></span>
  <br>
  <div id='gao'></div>
  <lable></lable>
  <input type="submit" id='calc' value='计算'>
  <br>
  <lable>面积</lable>
  <input type="text" id='area' disabled>
  <br>
  <lable>周长</lable>
  <input type="text" id='preimeter' disabled>
  <br>
</form>
<script src='//apps.bdimg.com/libs/jquery/2.1.4/jquery.min.js'></script>
<script src='./main.js'></script>
</body>
</html>
